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53 questions
The diagram depicts the process of crossing over, which occurs between homologous chromosomes during gamete formation.
What is the result of this process?
An increase in offspring variation
The deletion of amino acids in proteins
An increase in mutations in genetic material
The production of gametes that are genetically identical
In a particular species of mice, a single gene (B or b) determines tail length. The short-tail allele is sex-linked and dominant. Shading in the pedigree below indicates that an individual has a short tail. The pedigree shows the pattern of inheritance of the short-tail allele over three generations of mice.
Individual 6 is female. What is the genotype of individual 6?
XBXb
XbXb
XBY
XbY
Which statement describes crossing over as it occurs in meiosis?
The alleles of the gene separate
Spindle Fibers pull apart sister chromatids.
Genes moves to opposite ends of the chromosomes.
Homologous chromosomes exchange segments of DNA.
Which method do scientists use to confirm that crossing over occurs?
cloning
dihybrid crosses
gel electrophoresis
genetic engineering
A student is studying feather color inheritance in a certain species of chickens observes that the chickens that have black (homozygous), blue (heterozygous), or white (homozygous) feathers. The student hypothesizes that the feather color traits follows the incomplete dominance inheritance pattern.
Which data table would support the student's hypothesis?
In Labrador retriever dog, the black coat color allele (B) is dominant over the chocolate coat color allele (b). However, some litters produce dogs that have a yellow coat color. Scientists have determined this is because of a second gene that can influence coat color. If this eumelanin gene is recessive for both is recessive for both alleles (e), the dog's coat will be yellow regardless of the alleles for the other coat color gene.
A dog breeder sets up a cross between a dog that is homozygous dominant for color (BB) and heterozygous for eumelanin (Ee) with a dog that is homozygous recessive for coat color (bb) and heterozygous for eumalanin (Ee).
Place the dogs in the Punnett sqaure to show the color coat that would result from this cross.
1.) You may use each dog more than once
2.) You should fill all the blank boxes in the Punnett Square.
The diagram shows four different cells from the same animal.
Which statement about the cells is accurate?
The four cells have identical DNA sequences.
Cell 3 and Cell 4 have the longest DNA sequences because they have longer shapes.
The four cells are different shapes because they come from different parent organisms.
Cell 1 and Cell 2 have all of the same active genes even though they are from different body systems.
"CGTAACC” in the DNA box; AND “UGCAUUGG” in the mRNA box
“ACGTATCC” in the DNA box; AND “UGCAUAGG” in the mRNA box
“ACGTTGGC” in the DNA box; AND “UGCAACCG” in the mRNA box
“ACGTACCC” in the DNA box; AND “UGCAUGGG” in the mRNA box
“TBCTACCC” in the DNA box; AND “ACGAUGGG” in the mRNA box
From an evolutionary perspective, what is the significance of reproductive isolation developing between two populations within a species?
Speciation due to reproductive isolation in extinction of the ancestral species.
When two population cannot interbreed, the flow of genetic information between them stops.
Over time, reproductive isolation leads to increasing competition between the populations.
When the size of breeding populations decreases, the mutation rate decreases resulting in greater fitness.
How does natural selection affect populations?
By creating variation individuals that allows them to better adapt to changing environmental conditions.
By increasing the rate of beneficial mutations which allow individuals to increase their rate of reproduction.
By reducing variation between individuals in a population thereby making the population more homogeneous and likely to survive.
By acting on variations between individuals that make some better adapted to their environment and more likely to survive and reproduce.
Scientists construct the cladogram shown, of plants in the genus Clusia, based on evidence collected from DNA analysis.
Which conclusion is supported by the cladogram?
C valerioi and C. rosea are the most closely related of the four species.
C. rosea and C. cylindrica are the most closely related of the four species.
C. cupulata and C. valerioi are the most closely related of the four species.
C. cupulata and C. cylindrica are the most closely related of the four species.
How is chemosynthesis different from photosynthesis
Chemosynthesis does not require enzymes.
Chemosynthesis can occur in environments without sunlight.
Chemosynthesis does not require reactants from outside the cell.
Chemosynthesis produces sugars that organisms use as an energy source.
A group of students studied four different cell specimens under a microscope and recorded information about each cell in this table.
Which cell is a prokaryote?
Cell 1
Cell 2
Cell 3
Cell 4
A bacterium was discovered in several hot springs. The temperature of the springs can range 50 to 80 degrees Celsius. Scientists investigate an enzyme from this bacterium. They set up the data table shown to record their results.
Which question could be answered using the data collected?
How does the enzyme's shape change over time?
How does temperature affect the rate of the enzyme?
How does substrate concentration affect the reaction rate of the enzyme?
How does the active site of the enzyme change with different temperatures?
A bacterium was discovered in several hot springs. The temperature of the springs can range 50 to 80 degrees Celsius. Scientists investigate an enzyme from this bacterium. They set up the data table shown to record their results.
What is a reasonable hypothesis for this study?
Activation energy will be lowest in tubes 2 and 3.
The enzymes's shape will adapt to each temperature setting.
The enzyme's reaction rate will be greatest from 0 to 5 minutes.
The optimum reaction rate of this enzyme will be seen in tube 4 or 5.
Which molecule was coded for by the longest piece of DNA, assuming that no post-transcriptional RNA processing or slicing has occurred?
a protein with 25 amino acids.
a polysaccharide with 60 sugars.
a mRNA molecule with 20 codons.
an mRNA molecule with 45 nucleotides.
A mutation occurs in the DNA base sequence GGG GAG TTA, resulting in the base sequence GGA GAG TTA. Use the information in the table to determine the effect of this mutation on the amino acid chain produced.
What is the effect, if any, of this mutation on the amino acid chain produced?
Proline is now lysine and leucine is unchanged.
Proline is now lysine and asparagine is unchanged.
Proline is unchanged and asparagine is unchanged.
Proline is unchanged and leucine is now phenylalanine.
Some bacteria have developed a resistance to antibiotics through random mutations. One such mutation allows bacteria to produce enzymes that inactivate the antibiotics when they enter the bacteria.
Which statement describes how this mutation occurs?
The mutation occurs when nucleic acids are replicated.
The mutation occurs in chloroplasts during photosynthesis.
The mutation occurs in mitochondria during cellular respiration.
The mutation occurs when molecules move across the cell membrane.
Some orders of land and marine mammals are closely related. Molecular data recently collected from dolphins, camels, deer, and hippopotamuses have shown that hippopotamuses are the closest living relatives of dolphins.
Which cladogram models this evolutionary relationship?
How could genetic engineering be used to produce a more successful crop in a hot, dry climate?
non-essential DNA could be removed from the genomes of the crop plants.
DNA from plants adapted to dry areas could be added to the genomes of the crop plants.
RNA from a variety of nonagricultural plants could be added to the genomes of the crop plants.
mRNA transcripts of genes from dry weather crops could be added to the fertilizer used on the crop plants.
A biologist conducting a long-term field study noticed there were two types of mice in a valley. One type of mouse had webbed toes, and one type of mouse lacked webbed toes. A dam was built in the valley turning the land into a wetland. As the years passed, all mice living in the valley were found to have webbed toes. No mice were found with non-webbed toes.
Which statement best explains the observed change in the mouse population?
Webbed toes in mice are controlled by the environment.
The mice grew webbing to move more efficiently in their new environment.
Webbed-toed mice survived better and reproduced more than mice without webbed toes.
The increase in water levels in the valley increased the mutation rate in mouse population.
In most species, scientists have observed that related individuals share about 80% of the same genes. Cheetahs today, however, are known to share 99% of the same genes.
What does this lack of genetic diversity imply about the history of the cheetah population?
Cheetahs have never experienced mutations.
Cheetahs have experienced reproductive isolation.
Cheetahs inbred with other large cat species.
Cheetahs share a common ancestor with other large cat species
Rabbits were introduced to Australia in the 1800s. They rapidly overpopulated because they had few natural predators in the area. To control their population, scientists introduced a rabbit-specific virus into the population and their numbers greatly decreased. However, after several generations, the rabbit population began to increase again.
Which statement explains the new increase in the number of rabbits?
The rabbits interbred with the native rabbit species.
Some rabbits have natural immunity to the virus.
Some rabbits learned to survive even though they were sick.
The rabbits were able to have more offspring by changing their reproductive cycles.
Which species in the food web would be subject to the greatest biomagnification of pesticides applied to the grasses?
Deer
Grasses
Grasshoppers
Hawks
Which type of macromolecule stores energy and provides thermal insulation for the body?
Lipid
Protein
Nucleic acid
Carbohydrate
Which structural feature of the cell membrane allows molecules such as oxygen and carbon dioxide to diffuse into and out of the cell?
The cell membrane contains protein molecules.
The cell membrane contains cholesterol molecules.
The cell membrane is made up of two layers of phospholipids.
The cell membrane is anchored to the cytoplasm by the cytoskeleton.
The presence of which structure helps classify an organism as eukaryotic?
nucleus
cell wall
flagellum
chromosome
Which pair of organelles works together to give structure and support in animal cells?
cell wall and cytoplasm
cytoskeleton and Golgi complex
cell membrane and cytoskeleton
endoplasmic reticulum and cell membrane
Chief cells are found in the glands that line the inside of the stomach. These cells secrete large amounts of enzymes to aid in food digestion.
Which cellular structure will be more abundant in chief cells because of their high rate of enzyme reaction?
endoplasmic reticulum
nuclear envelope
cytoskeleton
cell wall
A student is asked to draw four cells.
Which drawing is a representation of a prokaryotic cell?
A scientist examines a fruit fly gene involved in the regulation of body development. A section of the DNA sequenced for the gene is is shown.
Which amino acid sequence be produced from the DNA?
Gly-Pro-Ser
Thr-Leu-Val
Gln-Gly-Trp
Trp-Asn-Gln
A scientist examines a fruit fly gene involved in the regulation of body development. A section of the DNA sequenced for the gene is is shown.
Which mRNA sequence was used to create the amino acid sequence? (Thr-Leu-Val)
UCC-TTC-GTT
ACC-TTG-GTT
CAA-GGT-TGG
ACC-UUG-GUU
Complete the blank cladogram using the information in the salamander distribution map and accompanying explanatory text.
Select the correct sequence from left to right.
L, N, O, P, M
M, O, P, N, L
L, O, P, N, M
L, M, N, O, P
Based on the salamander distribution data shown on the map, choose two salamander subpopulations which gene flow can occur.
L and N
M and O
O and P
M and N
L and P
Which two salamander subpopulations would be least likely to reproduce successfully if brought together?
Salamanders L and M
Salamanders L and N
Salamanders P and N
Salamanders P and O
The diagram shows the nucleus and the cytoplasm of a cell.
Identify the nucleic acid most commonly found in the nucleus, the nucleic acid that carries information from the nucleus into the cytoplasm, and the nucleic acid that carries amino acids in the cytoplasm.
What is the correct order
DNA in top box, mRNA in the center box and tRNA in the bottom box.
mRNA in top box, tRNA in the center box and DNA in the bottom box.
tRNA in top box, DNA in the center box and mRNA in the bottom box.
Scientists have found an allele of a plant gene that may protect plants from some types of insects. To determine whether this allele is present in other plants of the species or is a recent mutation, they conducted the following experiment.
Isolate a sample of dexyribonucleic acid (DNA) know to contain the allele from one plant that is unaffected by insects. Isolate a sample of DNA that may contain the allele from three plants of the same species growing in the same location. Treat the resistant DNA sample and the three DNA samples from the other plants with the same restriction enzymes to generate smaller segments of DNA. Load and run a gel electrophoresis to separate the DNA segments. Analyze the results of the gel electrophoresis.
Select the DNA sample(s) that has the same allele as the resistant plant.
The table shows the number of amino acid differences among organisms A through E for a common protein with 113 amino acids. Use the data in the table to complete the cladogram by placing an organism label in each blank box. Select the proper order from the choices
B in top box, C in 2nd box from the top, E in the box below D and A in the bottom box
A in top box, B in 2nd box from the top, C in the box below D and E in the bottom box
A in top box, E in 2nd box from the top, C in the box below D and B in the bottom box
C in top box, B in 2nd box from the top, A in the box below D and E in the bottom box
DNA sequences for a number of bird families in the order Passeriformes are shown. Differences in the DNA sequences between the Ptiloris family and other in this order are highlighted in red. An incomplete phylogenetic tree that notes important differences in the DNA among these bird families is also shown. Us the DNA sequence to complete the phylogenetic tree.
Use the families listed to complete the phylogenetic tree.
Manucodia in the top box; Empidonax in the middle box; and Diphyllodes in the bottom box
Diphyllodes in the top box; Manucodia in the middle box; and Empidonax in the bottom box
Empidonax in the top box; Diphyllodes in the middle box; and Manucodia in the bottom box
A scientist studies a population of lizards to determine whether or not the population is evolving.
Select the condition that would cause the population to be in a Hardy-Weinberg equilibrium?
Select "Mating is random." and "The lizard population is small."
Select "Mating is random." and "No lizards migrate in or out of the population."
Select "No lizards migrate in or out of the population." and "Natural selection is not occurring in the population."
Select "A new mutation occurs within the population." and "The lizard population is small."
Select "Mating is random." and "Natural selection is not occurring in the population."
A scientist studies a population of lizards to determine whether or not the population is evolving.
Select the correct word or phrase to place into the blank boxes to describe what occurs in when Hardy-Weinberg condition are met.
"for an individual" in the first box and "change" in the second box.
"in a population" in the first box and "change" in the second box.
"for an individual" in the first box and "remain constant" in the second box.
"in a population" in the first box and "remain constant" in the second box.
A population of stone crabs is composed equally three phenotypes:
dark brown (BB)
medium brown (Bb)
light brown (bb)
The crabs' color is controlled by incomplete dominance. An introduced crab predators favors medium brown crabs, while avoiding the dark crabs and light brown crabs. Predict how this selection pressure will affect the relative frequencies of B and b alleles in future generations of crabs. Assume all other selection pressure remain the same, and that there is no migration of crabs into or out of the population.
Predict the proper labels that match up with the picture
No change in both
Decrease in both
Increase in both
Three identical red blood cells, in side view, are placed in three different salt water solutions, as shown in the diagram. Predict the net flow of the water (H2O) into or out of each cell. Assume the volume pictured inside the red blood cell is the same as the volume outside the cell.
Place the correct picture in each blank box to show the next flow of water into or out of each cell
From left to right: "H2O out", H2O in" and "H2O in/out"
From left to right: "H2O in", H2O in/out" and "H2O out"
From left to right: "H2O in/out", H2O out" and "H2O in"
Three identical red blood cells, in side view, are placed in three different salt water solutions, as shown in the diagram. Predict the net flow of the water (H2O) into or out of each cell. Assume the volume pictured inside the red blood cell is the same as the volume outside the cell.
Place the correct picture in each blank box to show what will happen yo the structure of each cell after water movement occurs.
From left to right: "No effect", "Burst", "Shrivel"
From left to right: "Burst", "Shrivel", "No effect"
From left to right: "Shrivel", "Burst", "No effect"
From Left to Right: "ATP Pump", "Channel", "Phospholipds"
From Left to Right: "Channel", "Phospholipds", "ATP Pump"
From Left to Right :"Phospholipds", "ATP Pump", "Channel",
Identify the proper labels for the boxes in A and the box in B?
For Part A: “Pyruvate” and “O2” and Part B: “30º C”
For Part A: “Ethanol” and “CO2” and Part B: “20º C”
For Part A: “Ethanol” and “CO2” and Part B: “35º C”
For Part A: “Ethanol” and “H2O” and Part B: “40º C”
species 4 and species 5
species 5 and species 6
species 2 and species 4
species 2 and species 6
Hybrid DNA will separate easily when two species share more common ancestors.
Similar temperatures are needed to separate DNA from species that share more genetic similarities
Higher temperatures are needed to separate hybrid DNA from two species with greater differences in genomes.
Species that have diverged from a common ancestor more recently will also share more complementary base pairs.
Which two species of the smallest clade would include Species X?
Top box and bottom box
Top box and middle box
Middle Box and Bottom box
Where on the picture do "Species X" and "Species Y" go?
"Species X" goes in box 3 and "Species Y" goes in either box 1 or box 2.
"Species X" goes in box 1 and "Species Y" goes in either box 3 or box 4.
"Species X" goes in box 2 and "Species Y" goes in either box 3 or box 4.
"Species X" goes in box 4 and "Species Y" goes in either box 1 or box 2.
Using the information in the table place the list the species numbers in order from left to right of how they would so up on the cladogram to show relationships among species.
1, 2, 3, 4, 5,
2, 4, 1, 3, 5,
5, 4, 3, 2, 1
5, 2, 3, 4, 1
1, 3, 5, 2, 4
Which statement is supported by the data?
No competition for food exists within any of the three bird species.
At least three different species of worms are eaten by the three bird species.
Selection pressure from the three bird species will results in a worm population with only small and large worms
Less competition between the three bird species will be observed if a range of differently sized worms is available.
In reality, natural environments will always have resource limitations. Which graph realistically predicts growth for a natural squirrel population with no predators?
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